What is the Limit of f(x) as x Approaches Zero in the Interval [-1,1]?

In summary, the given setup can be interpreted as an epsilon form and the limit of f(x) as x goes to zero is 4. This can be seen by observing that f(x) is always between 4- x^2 and 4+ x^2, which both approach 4 as x gets smaller. It may be helpful to understand the concept of a limit intuitively in order to fully grasp this problem.
  • #1
daytrader
4
0
if 4-x^2 < f(x) < 4 + x^2 for x in [-1,1] then what's lim as x goes to zero of f(x) ...

this setup looks like epsilon form .. not sure how to interpret this guy...
 
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  • #2
Is it not just 4? Since f(x) is bounded by the two curves (see picture attached).

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  • #3
double checked it. the have it right. any ideas?
 
  • #4
Ideas about what? You have already been told that the limit is 4. That should be obvious from the "sandwiching" property. f(x) is always between 4- x2 and 4+ x2 and they both go to 4.
 
  • #5
may be I don't understand the problem to begin with.. can you explain. thanks
 
  • #6
Just think of it intuitively. What happens to the given bounds on f as x gets smaller and smaller (approaching zero)? Don't worry about any particular theorems, if you don't understand what is going on here you need to revisit the intuitive concept of a limit.
 

FAQ: What is the Limit of f(x) as x Approaches Zero in the Interval [-1,1]?

What does the limit of a function represent?

The limit of a function represents the value that the function approaches as the input value gets closer and closer to a specific value or point. In other words, it shows the behavior of the function at a particular point.

How is the limit of a function calculated?

The limit of a function can be calculated using various methods, including algebraic manipulation, graphing, and numerical approximation. The most commonly used method is the algebraic approach, where the function is simplified and evaluated as the input value approaches the specified point.

Why is it important to find the limit of a function?

Knowing the limit of a function is crucial in understanding its behavior and properties. It helps determine if the function is continuous, differentiable, and to what extent it is defined. The concept of limits is also used in many areas of mathematics and science, such as calculus, physics, and engineering.

What does it mean for a function to have a limit as x approaches zero in the interval [-1,1]?

If a function has a limit as x approaches zero in the interval [-1,1], it means that the function approaches a single value as the input value approaches zero within the given interval. This does not necessarily mean that the function is defined or continuous at x=0, but rather that it has a well-defined behavior near that point.

Can a function have different limits as x approaches zero in different intervals?

Yes, a function can have different limits as x approaches zero in different intervals. This is because the limit of a function depends on the behavior of the function in that specific interval. For example, a function may have a limit of 2 as x approaches zero in the interval [0,1] but have a limit of 4 as x approaches zero in the interval [0,2].

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